2 Copyright (C) 2002-2004 Paul Davis
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 #ifndef __ardour_audioengine_h__
21 #define __ardour_audioengine_h__
24 #include "libardour-config.h"
34 #include <glibmm/threads.h>
36 #include "pbd/signals.h"
37 #include "pbd/stacktrace.h"
39 #include "ardour/ardour.h"
40 #include "ardour/data_type.h"
41 #include "ardour/session_handle.h"
42 #include "ardour/libardour_visibility.h"
43 #include "ardour/types.h"
44 #include "ardour/chan_count.h"
45 #include "ardour/port_manager.h"
47 #ifdef HAVE_JACK_SESSION
48 #include <jack/session.h>
62 class AudioBackendInfo;
64 class LIBARDOUR_API AudioEngine : public SessionHandlePtr, public PortManager
68 static AudioEngine* create ();
70 virtual ~AudioEngine ();
72 int discover_backends();
73 std::vector<const AudioBackendInfo*> available_backends() const;
74 std::string current_backend_name () const;
75 boost::shared_ptr<AudioBackend> set_default_backend ();
76 boost::shared_ptr<AudioBackend> set_backend (const std::string&, const std::string& arg1, const std::string& arg2);
77 boost::shared_ptr<AudioBackend> current_backend() const { return _backend; }
78 bool setup_required () const;
80 ProcessThread* main_thread() const { return _main_thread; }
82 /* START BACKEND PROXY API
84 * See audio_backend.h for full documentation and semantics. These wrappers
85 * just forward to a backend implementation.
88 int start (bool for_latency_measurement=false);
89 int stop (bool for_latency_measurement=false);
90 int freewheel (bool start_stop);
91 float get_dsp_load() const ;
92 void transport_start ();
93 void transport_stop ();
94 TransportState transport_state ();
95 void transport_locate (framepos_t pos);
96 framepos_t transport_frame();
97 framecnt_t sample_rate () const;
98 pframes_t samples_per_cycle () const;
99 int usecs_per_cycle () const;
100 size_t raw_buffer_size (DataType t);
101 pframes_t sample_time ();
102 pframes_t sample_time_at_cycle_start ();
103 pframes_t samples_since_cycle_start ();
104 bool get_sync_offset (pframes_t& offset) const;
106 int create_process_thread (boost::function<void()> func);
107 int join_process_threads ();
108 bool in_process_thread ();
109 uint32_t process_thread_count ();
111 bool is_realtime() const;
112 bool connected() const;
114 int set_device_name (const std::string&);
115 int set_sample_rate (float);
116 int set_buffer_size (uint32_t);
117 int set_interleaved (bool yn);
118 int set_input_channels (uint32_t);
119 int set_output_channels (uint32_t);
120 int set_systemic_input_latency (uint32_t);
121 int set_systemic_output_latency (uint32_t);
123 /* END BACKEND PROXY API */
125 bool freewheeling() const { return _freewheeling; }
126 bool running() const { return _running; }
128 Glib::Threads::Mutex& process_lock() { return _process_lock; }
130 int request_buffer_size (pframes_t samples) {
131 return set_buffer_size (samples);
134 framecnt_t processed_frames() const { return _processed_frames; }
136 void set_session (Session *);
137 void remove_session (); // not a replacement for SessionHandle::session_going_away()
138 Session* session() const { return _session; }
140 class NoBackendAvailable : public std::exception {
142 virtual const char *what() const throw() { return "could not connect to engine backend"; }
145 void split_cycle (pframes_t offset);
147 int reset_timebase ();
149 void update_latencies ();
151 /* this signal is sent for every process() cycle while freewheeling.
152 (the regular process() call to session->process() is not made)
155 PBD::Signal1<int, pframes_t> Freewheel;
157 PBD::Signal0<void> Xrun;
159 /* this signal is emitted if the sample rate changes */
161 PBD::Signal1<void, framecnt_t> SampleRateChanged;
163 /* this signal is sent if the backend ever disconnects us */
165 PBD::Signal1<void,const char*> Halted;
167 /* these two are emitted when the engine itself is
171 PBD::Signal0<void> Running;
172 PBD::Signal0<void> Stopped;
174 static AudioEngine* instance() { return _instance; }
175 static void destroy();
178 /* The backend will cause these at the appropriate time(s)
180 int process_callback (pframes_t nframes);
181 int buffer_size_change (pframes_t nframes);
182 int sample_rate_change (pframes_t nframes);
183 void freewheel_callback (bool);
184 void timebase_callback (TransportState state, pframes_t nframes, framepos_t pos, int new_position);
185 int sync_callback (TransportState state, framepos_t position);
186 int port_registration_callback ();
187 void latency_callback (bool for_playback);
188 void halted_callback (const char* reason);
190 /* sets up the process callback thread */
191 static void thread_init_callback (void *);
193 /* latency measurement */
195 MTDM* mtdm() { return _mtdm; }
196 MIDIDM* mididm() { return _mididm; }
198 int prepare_for_latency_measurement ();
199 int start_latency_detection (bool);
200 void stop_latency_detection ();
201 void set_latency_input_port (const std::string&);
202 void set_latency_output_port (const std::string&);
203 uint32_t latency_signal_delay () const { return _latency_signal_latency; }
205 enum LatencyMeasurement {
211 LatencyMeasurement measuring_latency () const { return _measuring_latency; }
216 static AudioEngine* _instance;
218 Glib::Threads::Mutex _process_lock;
219 Glib::Threads::Cond session_removed;
220 bool session_remove_pending;
221 frameoffset_t session_removal_countdown;
222 gain_t session_removal_gain;
223 gain_t session_removal_gain_step;
226 /// number of frames between each check for changes in monitor input
227 framecnt_t monitor_check_interval;
228 /// time of the last monitor check in frames
229 framecnt_t last_monitor_check;
230 /// the number of frames processed since start() was called
231 framecnt_t _processed_frames;
232 Glib::Threads::Thread* m_meter_thread;
233 ProcessThread* _main_thread;
236 LatencyMeasurement _measuring_latency;
237 PortEngine::PortHandle _latency_input_port;
238 PortEngine::PortHandle _latency_output_port;
239 framecnt_t _latency_flush_frames;
240 std::string _latency_input_name;
241 std::string _latency_output_name;
242 framecnt_t _latency_signal_latency;
243 bool _stopped_for_latency;
244 bool _started_for_latency;
247 void meter_thread ();
248 void start_metering_thread ();
249 void stop_metering_thread ();
251 static gint m_meter_exit;
253 typedef std::map<std::string,AudioBackendInfo*> BackendMap;
254 BackendMap _backends;
255 AudioBackendInfo* backend_discover (const std::string&);
256 void drop_backend ();
259 } // namespace ARDOUR
261 #endif /* __ardour_audioengine_h__ */